Belgium’s Peppol Framework for E-Invoicing: Compliance & Connectivity

Belgium is making electronic invoicing mandatory for all B2B transactions starting in 2026. This shift goes beyond simply using a digital invoice format and generate the electronic invoice which is structured and machine readable. For this, the Belgian government is adopting the Peppol interoperability framework as the core infrastructure for sending and receiving e-invoices. This interoperable networked approach ensures that every business regardless of their chosen software can exchange e-invoices efficiently, securely, and in compliance with the law. 

The Peppol interoperability framework allows businesses to connect through any Peppol compliant service provider to send and receive e-invoices between trading partners, and every company registered on the network.

What is the Peppol Interoperability Framework?

Peppol stands for Pan-European Public Procurement Online. It is not a software, but a set of international standards and a network that enables secure and structured electronic document exchange between businesses and public bodies. The Peppol Interoperability Framework is the set of rules, technical standards, and operational processes that make this open exchange possible across multiple providers and platforms.

The framework is designed so that any company, using any Peppol compliant software or service, can send an electronic invoice to any other company on the Peppol network. It eliminates the need for bespoke integrations or locked-in platforms enabling “plug-and-play” interoperability between organizations.

How the Framework Works in Belgium’s E-invoicing Mandate

The government chose the Peppol model because it removes technological barriers as its widely known framework for e-invoicing. Businesses connect to the Peppol network through certified service providers known as Access Points. These Access Points take care of the technical details, from formatting and validation to secure delivery.

Here is how the entire Peppol Interoperability Framework

1. The business creates an electronic invoice using Peppol-compliant invoicing software or an ERP system.
2. The invoice is formatted automatically into the Peppol BIS (Business Interoperability Specification) standard, ensuring all required fields and structures are included.
3. The invoice is sent to the company’s chosen Peppol Access Point (AP) also called Peppol Accredited Service provider like ClearTax.
4. The Access Point validates the invoice for compliance with the Peppol BIS format and Belgian regulations.
5. The Access Point checks the Peppol central registry (SMP) to locate the recipient’s Access Point using the recipient’s unique identifier (usually their VAT or enterprise number).
6. The invoice is securely delivered over the Peppol network from the sender’s Access Point to the recipient’s Access Point.
7. The recipient’s Access Point receives the invoice, verifies its integrity, and delivers it to the recipient’s accounting or ERP system.
8. The recipient reviews and processes the invoice in their system, often with minimal manual intervention.
9. Both sender and recipient can track the delivery and status of the invoice.

Understanding the Peppol 4 Corner Model

At the core of the Belgium Peppol Interoperability Framework is the Peppol 4 Corner Model.  The Peppol 4 Corner Model is a network structure that connects senders and receivers of e-invoices through their chosen service providers, known as Access Points. Instead of requiring both parties to use the same software or a single centralized platform, each party connects through their own Access Point, which handles communication using Peppol’s standardized protocols.

The four “corners” are:

1. Sender (Corner 1): The business or organization issuing the e-invoice.
2. Sender’s Access Point (Corner 2): The certified Peppol service provider or software sending documents on behalf of the sender.
3. Receiver’s Access Point (Corner 3): The certified Peppol service provider or software receiving documents for the recipient.
4. Receiver (Corner 4): The business or organization receiving the e-invoice.

Note: There is also the Peppol 5 Corner model, also called Decentralized Continuous Transaction Controls (CTCs), which will be used when the e-reporting mandate is implemented in Belgium in 2028. This will add the Belgian government as the fifth corner, and all e-invoice data will be submitted to authorities in real time.

Key Components of the Peppol Interoperability Framework

Below are the essential building blocks that make the Peppol interoperability framework effective and reliable for e-invoicing compliance in Belgium:

1. Peppol Access Points (APs): Certified service providers that send and receive invoices on behalf of businesses. Access Points convert invoices into Peppol BIS format, validate them, and deliver them securely to the right recipient.
2. Peppol BIS Format: The standardized XML invoice structure that every Access Point must support. This ensures all invoices contain the necessary data in a uniform format, following EU and Belgian rules.
3. Central Registry (SMP): The Service Metadata Publisher (SMP) acts as a directory of all participants and their identifiers. In Belgium, this usually uses VAT or enterprise numbers, allowing unambiguous routing.
4. Interoperability Rules: The framework sets out strict technical protocols (like AS4) and security measures for all Access Points. These ensure secure, traceable, and error-free document exchange.
5. Validation and Error Handling: Access Points validate invoices before sending, ensuring all required fields are present and in the right format. If an invoice fails validation, it is rejected immediately, and the sender is notified, reducing compliance risk.
6. No Central Government Portal: Unlike some countries, Belgium does not require all invoices to pass through a government-run platform. Instead, compliance is achieved through the open Peppol network, keeping control with businesses while maintaining a high standard of interoperability and oversight.
7. Continuous Monitoring and Improvement: Peppol is overseen by OpenPeppol and national authorities, with regular updates to standards and protocols, ensuring ongoing security and effectiveness.

Why Peppol for Belgium’s E-invoicing Mandate?

Belgium selected the Peppol interoperability framework to support its e-invoicing law for several practical reasons:

• Universal coverage: Peppol provides “connect once, reach all” functionality. Any business connected to Peppol can send and receive invoices with any other participant, no matter which software or provider they use.
• Open, competitive market: By requiring interoperability, Belgium ensures that businesses can choose the e-invoicing solution that best fits their needs, without being locked into a single vendor or government portal.
• No Central Portal Needed: Unlike centralized systems, Belgium’s adoption of the Peppol 4 Corner Model within its interoperability framework means there is no single government-run platform. Instead, compliance is achieved through this decentralized, open network.
• International alignment: Peppol is used across Europe and in countries like Australia, Singapore, and New Zealand. Using the same framework sets up Belgian businesses for seamless cross-border invoicing.
• Security and reliability: The network’s rules ensure every invoice is delivered securely, only to the correct recipient, and cannot be tampered with in transit.
• Automatic compliance: Since Peppol Access Points handle validation and formatting, businesses are assured their invoices meet both Belgian and European legal standards.

Conclusion

Belgium has mandated Belgium Peppol interoperability framework  to create an open, secure, and standardized network for e-invoice exchange. This ensures that every business—regardless of software or ERP they are using can send and receive structured, machine-readable invoices seamlessly with any trading partner, using certified Peppol Access Points.

By adopting Peppol, Belgian companies gain access to a vast digital ecosystem that simplifies compliance, enhances business efficiency, and supports future growth both domestically and internationally. In practical terms, connecting to Peppol is now a necessity for every Belgian VAT registered business.